A Louisiana State Penitentiary at Angola correctional officer stood by in January 2014 while other guards severely beat a handcuffed-and-shackled Angola inmate being held in solitary confinement, according to charges filed this week by federal prosecutors in Baton Rouge in an ongoing probe.

Scotty Kennedy, who according to his attorney resigned in February 2014, plotted with those guards to cover up the "unjustified assault" by concocting a false story, falsifying prison records to corroborate the story, and tampering with witnesses and physical evidence, according to a bill of information filed against him Thursday.

Kennedy faces two felony counts: deprivation of rights under color of law and conspiracy to obstruct justice. The bill of information alleges Kennedy deprived the inmate, who suffered "significant injuries," of the right to be free from cruel and unusual punishment.

"The civil rights investigation regarding the allegations charged in the bill of information is ongoing," U.S. Attorney Walt Green said Friday.

Prosecutors charged Kennedy in the bill of information after he waived his right to have the charges presented to a federal grand jury.

"Mr. Kennedy is part of an ongoing federal investigation, and he has made the right decision to take responsibility for his role early," Kennedy's attorney, Michael Fiser, said.

Department of Public Safety and Corrections spokesman Ken Pastorick said DPSC initiated the investigation and referred it to the FBI.

"We have cooperated with FBI investigators throughout this process," he said, noting that DPSC "takes very seriously the safety and welfare of all employees and offenders, and doesn't tolerate any actions which compromise safety."

The bill of information identifies the inmate only by the initials J.S., and the other guards are referred to as officers A, C and D.

Kennedy had a clean record at the maximum-security prison before the January 2014 incident involving the inmate, but officers A and C had several excessive force complaints against them, the federal documents state.

Kennedy's charges are the latest black eye in nearly a year of turmoil in the state corrections department.

His charges came one day after two former high-ranking Angola officials surrendered to the West Feliciana Parish jail, accused of stealing at least $160,000 from an employee fund.

Burl Cain abruptly announced in December he would call it quits after two decades as Angola's warden following an investigation by The Advocate that revealed his business ties to a family member of an Angola inmate, and to the close friend of another inmate at the same prison.

Since then, his son, Nate Cain, stepped down from his post as warden of what is now called the Raymond Laborde Correctional Center in Cottonport. He and his wife, Tonia Cain, who resigned from her position as the lockup's business manager, are under criminal investigation on accusations of theft at that prison, formerly known as the Avoyelles Correctional Center.

TheFollow Joe Gyan Jr. on Twitter, @JoeGyanJr.